Generally, a battery pack is a kind of power supply that is charged with power (electric energy) received from an external charger and supplies the power so that portable electronic devices, such as cellular phones, personal digital assistants (PDAs) and the like can be operated, and consists of a battery cell which is charged with electric energy and circuits for charging and discharging the battery cell (supplying electric energy to portable terminals).
The electrical connection between the battery pack, which is used in the portable terminals, and the charger for charging electric energy to the battery pack may be achieved using a connector supply system, which receives the power from a regular power source and converts the voltage and current thereof to correspond to those of the battery pack, and supplies the electric power to the battery pack via a connector of the corresponding battery pack.
However, when the charger and the batteries are connected or disconnected to replenish the electric power of the batteries using such a connector supply system, there may be drawbacks, such as instant discharge owing to the difference in potential between the charger connector and the battery connector, the risk of fire and concomitant damage due to fire caused by the presence of foreign substances gathered on both connectors, and the like.
Further, accumulated humidity will cause the discharge of the battery through the battery connector and other problems will occur, such as the reduction in the life and performance of the battery pack, and the like.
To solve the above-mentioned problems, a non-contact charging system using a wireless power transmission and reception system was recently proposed.
Meanwhile, portable terminals that have recently proliferated include an electronic settlement system using a Local Area Network (LAN), so that settlement is carried out by bringing the portable terminals into proximity with electronic settlement devices and conducting a settlement process.
Such an electronic settlement system essentially includes a loop antenna, an absorber, an impedance matching circuit and the like in the portable terminal.
In order to mount, in a single portable terminal, both the non-contact charging system using the wireless power transmission and reception technology and the settlement system using the LAN, a power reception coil of the charging system and the loop antenna of the electronic settlement system should be mounted in the portable terminal and operated.
However, due to interference from harmonic components (n times a fundamental wave), which is produced in the frequency band (e.g. 13.56 MHz) of the electronic settlement system and the frequency band (e.g. hundreds kHz) of the charging system, problems such as the unstable transmission of signals occur, therefore failing to perform desired functions.
The information disclosed in this Background of the Invention section is only for the enhancement of understanding of the background of the invention and should not be taken as an acknowledgment or any form of suggestion that this information forms the prior art that would already be known to a person skilled in the art.